a) Field of the Invention
The invention relates to a system and method for assisting image-capturing device to focus and, more particularly, to a system and method for assisting fixed-focus image-capturing device to focus.
b) Description of the Related Art
In order to take clear and accurate pictures of an object to be photographed, a user must first, according to the functional characteristics of a camera or a video camera, find a photographable position, and then adjust the camera/video camera to focus on the object to be photographed, either manually by hand or automatically by camera itself, before pressing the shutter to obtain the sharp and clear image acquired by the user. Among the series of preparation steps, the most important thing is that the user must constantly monitor the viewfinder or the display screen of the camera/video camera, which shows the scene the camera/video camera is capturing, to ensure a good photographic result. Although over the years there are major breakthroughs in the camera industry, such as auto-focusing, focusing lens, digitization, etc., the process in taking a clear photograph is nevertheless similar to the abovementioned process.
With the conventional picture-taking process, it is inconvenient for a user to take pictures of a large quantity of a specific-type of objects, especially when the user must take pictures of different objects under a circumstance in which he/she cannot monitor the viewfinder/display screen, and the pictures taken as such usually come out blurry. Taking pictures by a notebook computer is a good example of that circumstance. Most notebook computers have built-in digital cameras (web camera), and these cameras can be moved along a fixed trajectory, which implies the possibility of mass photographing, and are much faster than scanners in terms of taking pictures. However, these cameras often do not have auto focus, and so a user has to position the object to be photographed at the focus distance of the camera through monitoring the viewfinder/display screen. But because the computer screen, which serves as the display screen, is blocked due to the folding of the computer panels, on one of which the camera is located and on another of which the object to be photographed may be placed, it would not be easy for the user to monitor the computer screen. Therefore, even if a user were to follow the abovementioned picture-taking steps, a clear image is hard to obtain from the web camera.
The invention is aimed to overcome the limitations described above. The problems to be solved include: assisting a fixed-focus image-capturing device to focus on an object to be photographed while the user is unable to monitor the viewfinder/display screen, automatically detecting placements of an object to be photographed, and automatically taking clear pictures of the object to be photographed.